In the perilous world of cephalopod romance, male blue-lined octopuses have evolved a shocking strategy to survive mating.

Scientists have found that male blue-lined octopuses inject venom and paralyse females during sex to avoid being killed and cannibalised by their much larger partners.

Male blue-lined octopuses inject females with venom during mating to avoid being eaten, temporarily paralyzing their partners, a new study has found. The blue-lined octopus (Hapalochlaena fasciata) is a small yet highly poisonous cephalopod commonly found in shallow reefs and tide pools.